"acid-fast" - inability to be gram-stained due to high concentration of mycolic acids. Classified as Gram (+)

What is a bacterial Capsule?

What are the functions of bacterial Capsules?

Determines virulence: limits ability of phagocytes to engulf the bacteria. Adherence of bacteria to human tissues

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What do bacterial Capsules allow us to do?

Lab identification (use of antiserum against the capsular polysaccharide). Capsular polysaccharides used as antigen in vaccines (capable of eliciting protective antibodies)

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How can Flagella help E.coli, Proteus sp.?

Propell the bacteria up the urethra into the bladder --> UTIs

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What is an example of Flagella being used for lab identification?

Salmonella sp. - identified by use of specific antibodies against flagellar proteins

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What are Pili?

Hairlike filaments that extend from the cell surface. Found mainly on Gram (-)

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What are the Functions of Pili?

Mediate the ATTACHMENT of bacteria to specific receptors on the human cell surface --> initiates infection. Forms attachment between donor and recipient bacteria during CONJUGATION and allow genetic exchange

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What is Glycocalyx?

Polysaccharide coating that is secreted by many bacteria. Covers surfaces like a film allowing bacteria to ADHERE firmly to various structures (skin, heart valves, catheters). Mediates adherence Strep mutans to surface of teeth --> forms plaque, precursor of dental carries

Which bacteria commonly use IgA Protease?

N. gonorrhea, S. pneumoniae, H. influenza

What do bacteria use for invasiveness?

How do some bacteria induce their own uptake into host cells?

Initiated by ligand-receptor interactions that activate host signaling with the actin cytoskeleton providing the necessary force to internalize the particle into a membrane-bound vacuole. Allows bacterial entry into protected niche and enabling pathogens to pass thru cellular barriers such as the intestinal epithelium or the blood-brain barrier

What are Endotoxins?

Integral parts of the cells walls of Gram Negative cocci and bacilli. Lipopolysaccharides that are low in toxicity. Cause some generalized effects of fever and shock (septic shock) mediated by release of cytokines such as IL-1 and TNF